Analog generation of an FM video signal for recording presents various problems, including aging of components, tolerances in the circuitry generating the carrier and the carrier deviation, and pre-emphasis circuitry which vary significantly from the nominal. Digital FM modulating techniques have, heretofore, been cumbersome requiring the use of a substantial amount of circuitry and excessive memory storage.
A feature of the invention is a digital synthesizer technique and system which avoids the disadvantages of analog modulation, without introducing the complexity of typical digital signal processing.